Hydraulic shock absorber



May 2s, 1931. LE ROY A- WESTMAN ET AL 1,807,362

HYDRAULIC SHOCK ABSAORBER FiledJan. 19, 1929 2 Sheets-Sheet 2 INVENTOR GLENN BLARHAN EY L: RuY Azwzsmnn x ATTORNEY Patented May 26, 1931 i UNITED lSTATESv PATENTOFFICE LE noir WESTMAN AND GLENN B. CARMAN, or CLEVELAND, omo

' HYDRAULIC SHGCK ABSORBER Application: filed January 19, 1,929. Serial No. 333,661. y

Our invention. relates tov hydraulic shock absorbers for spring supported vehicles, and the present invention yis an improvement in the` shock absorber shown and described in our co-pending application, Ser. No.f333,6 filed jJ an. 19, 1929. Thus,1the present structureis simplified tofacilitate the manufacture thereof, to permit convenient assemblyand adjustment of the parts, to-regulate and control the flow of the liquid `by relative movements between the parts, and to effect transfer of the liquid through vthe moving parts.

In the accompanyingdrawings, Fig. 1 is a sectional view verticallythrough the device showing the working parts' thereof `infa neutral position. Fig. 2 is asectionalview taken on line 2 2 of Fig. 1, vertically in the plane ofthe axis `of the device. Fig. 3 is a sectional view of the device .on horizontalline 3"-,3 of Fig-1. Fig.4 is a perspectiveview of. the channeled disk orV oscillatory member. Fig. 5 is a perspective view of the piston pivotally connected to the rear plate. .-Fig. 6 isa sectional view corresponding to Fig. 1,-but-showing a modified form of the invention. Fig. 7 is a sectional view in plan of the modified device, takenon line 7---7V ofFig. 6. Fig. `8 is a diagrammatic'viewof the device shown in Fig. 6,V with the diskl and piston'rotated to an angle ofapproximately 45.",and-Fig.'A 9 is a similar view of thel parts inthe device of Fig. l turned to the same angle.

- The present invention comprises a casing 2i' 'containing a circularl chamberv- 3 within which vadisk 4isadapted to be Aoscillatedor rotated in oppositedirections. U An operating shaftV 5 for disk 4 extends through a bearing'portion 6 on frontwall 8 of the casing, and a packing ring or .nut 9 `is screw-connectedV with the bearing portion to seal the joint. The rear or opposite sideofcasing 2I is closed bya plate l0 welded or `affixed to the wall of thecasing in any suitable way, and disk 4 is formed `with a straight guide-.way or'channel? diametrically across the same opposite plate l0.

A round post or stud shaft 11 on plate IO'eX-V tends into the groove or channel 7 on thever- `tical medianlineof the casing Vabove the-axis ofthe disk 0r in `offset or. eccentric relation thereto. VA square-block or flat,sided piece 12 is sleeved pivotally upon-post 11, 'and this block is confined within a rectangular slotflB in a reciprocable plate orpiston 14 which is seated `within the Vguide-ways or channel 7 in' the disk.' Slot 13 entends at right angles to channel 7 toward andacrossthe axis or center of the disk, and in turning the disk about its aXis, piston 14 is also caused to rotate about the same. aXisand to slide in the direction'of rotation. The Vpiston slides lengthwise` of the vchannelvand the rotatable/movement of the Vdisk carriesit at the same time toward the stationary post or stud shaft 1l. That is, when the disk is turned the piston isshifted lengthwise within channel and also moved or carried toward post 1l and block 12, thereby narrowingV or reducing v.the space'betwe'enf block 12 and the inner end 15 ofslot 13. The length of slotA 12 may be greateror less, but'as shown in the drawings, the slot is long enough topermit the disk to be rotated to no less than an angle ofapproximately 45, as indicated inthe diagrammatic views Figs. 8 and 49. :It being understoodV that relative movement occurs :between piston 14 and pivot Vblock 12 lengthwise of slot l13 e i turning movement Vof the disk,l it -will also `be understood that. l .theY relatively movable vparts may be utilized as slide valves to restrict or to cut olfthe flow of aI liquid passing throughslotl 13:. q For example, in Fig.

'during th ing 17in disk 4 where a tapering valve fmemberv 18 .is employed toV reducefthe passage. From this point duct1'9 extends through disk .4 toV one ,end'of channel 7,` thereby establishing open Vcommunication at all times between theopposite ends of channel 7 so thatthe liquid maybe transferred from one end cham- .ber .to the other by the reciprocable movements of piston 14. Moreover the. liquid flows through the piston itself where it may be controlled or cut off partly or completely by using block 12 as a valve member during the rotative movement of disk 4. The liquid also flows through transfer ducts and passages where it may be restricted in a predetermined degree at orifice 17, utilizing the tapered valve stem 18 for that purpose, see Fig. 2, as hereinafter more fully explained.

Valve stem 18 extends through an axial bore in shaft 5 and has a screw-threaded body 20 engaged with screw-threads to effect longitudinal movement of the valve relatively to the tapered seat at orifice 17. The outer end of member 18 projects beyond 'the outer end of shaft 5 and has a wrench engaging extremity to facilitaterotation and permit adjustment thereof, and a screw-threaded cap or coverv21 encloses the wrench 'extremity and seals the opening or'bore in the shaft. An arm or lever 22 is secured to the projecting end of shaft 5 wherewith theshaft and disk may be rotated or oscillated. This arm is linked or coupled to the vehicle axle or spring, and the casing 2 is bolted to the frame of the vehicle according to known or customary practices, whereby shaft 5 will be oscillated whenever the vehicle 'spring is flexed. p

In operation, when the vehicle spring is under its normal load, it is partly compressed and under tension. The working parts of the shock absorber device, in lthis condition of the vehicle spring, are in a centralor substantially neutral position, for example, as delineated in Fig. 1. Therefore, a'movement of the vehicle body or spring vertically in either direction 'will rotate the disk and shift the piston within its channel, thereby displacing theliquid opposite one 'end of the piston'and transferring it through the ducts and passages to the opposite end o-f the piston. The initial movement is free until block 12 cuts oif'port 16,and then the entire'flow of the 4liquidis through orifice 17. Thereafter g thevmovement of the vehicle'spring is controlled in fixed and'prede'termined degree by the restriction in flow of the liquid at oriflee 17 by valve member 18. Abnormalmovements 'of the vehicle spring or the vehicle body will increase-however the rotative Inove ment of the disk, and thereby produce a greater relative movement between piston 14 andpivot block 12,`th us causing the piston to'cut olf port 16 or orifice `17fingref1terfor lesser degree dependent upon the degree of rotative'm'ovement imparted to disk 4. Accordingly, additional restrictionin'the flow 'of theliquid between the opposite end of the piston is produced, thus vcheckingor "dampening the 'movement additionally propor- "tionateto the increased throw or movement ofthe vehicle body 'or'vehicle spring. To

vpromote that Ypurpose the position of the Vports'inthe piston, or thesize or'shape'fof the ports, maybe be changed'to meet 'any disk,

given need or requirement, and the present showing merely exemplifies one operating arrangement which may be used.

Another form of the invention is shown in Figs. 6 and 7, the modification being chiefly in the valve means for controlling the flow of the liquid through orilice`17. 'In this case valve member 18 is tubular and contains a ball vor check valve 23 in one end opposite an axial `end opening-and lateral openings which permit the liquid to flow freely through orifice 17 .into fand "through the tube. A screwthreaded stem extends through this tube to either limitthe `movement of ball 23 or to seat theballto close the end opening in the tube. I'nxthis form of the invention the liquid passes 'freely Iin one 'direction through the axial end 'opening past the ball, but is reduced Vin flovv'vvhen passing in the opposite direction to and through the tapered seat, inasmuch as the check valve willseat itself and close the end openingrunder the latter condition. Therefore this 'shock absorber may be readily'adj usted and-set to act with increased checking or dampening effect in one direction than in the other, orthe ball 23 may be held to its seat to'restrict the flow of the liquid equally inopposite directions. Port 16 in 'piston 14 inlthis instance is'so positioned in respectto block p12 that theilowof liquid through this port 'will be lrestricted additionallyand gradually in'increasing degreevdur* ing'the rotative movements of the disk, although the size of this port and its'position in :respect'to block 12imay be 'changed from that shown'in the drawings to modify'the results.

iWhat we'claim, is:

1. A 'shock absorber, including a liquid chamber, a `rotatable 'disk within said chamber'and axially aligned therewith, aneccentric device, anda liquid displacement piston operatively'connected*withvsaid diskfand said eccentric device,said'piston having a liquid transfer'passage assoc1ated with said device to restrain in varying degree the lflow of liqvuid displacedby the piston.

2. A shock absorber,includingal chamber containing a liquid, a transversely channeled disk rotatably'mounted Within said chamber, apiston slidably-mounted inthechannel of said disk and at'opposite ends openly exposed to 'the liquid within A'the channel of said `means for reciprocating said lpiston upon rotating said disk in opposite directions, said disk `and'pistonhaving transfer passages for'the liquid adapted to be opened and closed by saidY means to effect restrictioniin flow of the liquid during apart Vofthestroke of the piston.

3. A lshock absorber, rincluding a liquid chamber, a channeleid'disk rotatably mounted `within said chamber, a 4reciprocable piston mountedtoslide within said channeled disk, `4a'ireccentrc'device lcoe-acting with-'said disk to reciprocate saidv pistona liquid transfer passage extending through the piston in communication with the opposite ends of the channel in said disk, and means for restricting the flow of a liquid in at least one direction through said passage.

4. shock absorber, including a liquid casing, a rotatable member within said chamber, a reciprocable piston carried by said rotatable member, a pivot block for said piston located off-center in respect to the axis of said rotatable member, and a liquid transfer passage within said piston adapted to be closed by said block to restrict the flow of liquid displaced by the piston.

5. A shock absorber, including a liquid chamber, a rotatable disk and piston for displacing a liquid confined within said chamber, said piston being supported to slide 20 diametrically' across said disk, an eccentric post and a pivot block sleeved thereon and slidably engaged by said piston, and a liquid transfer passage having a port adapted` t be closed by said block for checking the disg placement of liquid by the movements of said disk and piston. Y

6. A shock absorber, including a chamber,

a channeled disk and a slotted piston adapted to rotate together within said chamber, an eccentric post having a pivot block in slidable` engagement with said slotted piston, a liquid passage adapted to be cut off by said block during the reciprocable movements of said piston, and adjustable means for restricting the flow of liquid through said passages.

7 A shock absorber, comprising a casing containing a rotatable disk and piston, an eccentric device for translating the rotary movement of the piston into a reciprocable movement, communicating passages in said disk, and piston, permitting the transfer of a liquid from one end of the piston to the other during rotatable movements of the disk, and the reciprocable movement of said piston being adapted to cut off said passages with valve eifect to control the said transfer of liquid.

8. A shock absorber, including a casing a rotatable disk within said casing and axially aligned therewith, a liquid displacement pis-` ton, eccentric means co-acting with said disk for reciprocating said piston, said piston and eccentric means co-acting as valve members to gradually restrict the amount of liquid displaced by a part of the stroke of the piston.

9. A shock absorber, including-a circular chamber, a rotatable disk channeled across its face, a piston adapted to slide within said channeleddisk, means for reciprocating said piston by oscillating said disk, communicating passages in said piston and disk to permit the transfer of a liquid from one end of the channel to the other during oscillatory movements of the disk, and means for restricting the flow of liquid through said passages.

10. A shock absorber, including a transversely channeled rotatable disk, a liquid displacing piston carried in the channel of said disk, eccentric means opposite said disk and co-acting therewith for reciprocating said piston, a liquid transfer port axially of said disk, and a valve member axially of the disk opposite said port for restraining the iow of liquid and the movements of said parts.

11. A shock absorber, including a channeled rotatable disk having an operating shaft, a reciprocable piston within the channel of said disk, eccentric means co-acting with said disk to operate said piston, a liquidpassage within said disk extending into theV tures.

GLENN B. CARMAN. LE ROY A. WESTMAN. 

